WATER

, in Physiology, a clear, insipid, and colourless
fluid, coagulable into a transparent solid substance,
called ice, when placed in a temperature of 32°
of Fahrenheit's thermometer, or lower, but volatile
and fluid in every degree of heat above that; and when
pure, or freed from heterogeneous particles, is reckoned
one of the four elements.

By some late experiments of Messrs. Lavoisier, Watt,
Cavendish, Priestley, Kirwan, &c, it appears, that
Water consists of dephlogisticated air, and inflammable
air or phlogiston intimately united; or, as Mr. Watt
conceives, of those two principles deprived of part of
their latent heat. And in some instances it appears
that air and Water are mutually convertible into each
other. Thus, Mr. Cavendish (Philos. Trans. vol. 74,
p. 128) recites several experiments, in which he changed
common air into pure Water, by decomposing it in
conjunction with inflammable air. Dr. Priestley likewise,
having decomposed dephlogisticated and inflammable
air, by firing them together by the electric
explosion, found a manifest decomposition of Water,
which, as nearly as he could judge, was equal in weight
to that of the decomposed air. He also made a number
of other curious experiments, which seemed to favour
the idea of a conversion of Water into air, without absolutely
proving it. The difficulty which M. De Lue
and others have found in expelling all air from Water,
is best accounted for on the supposition of the generation
of air from Water; and admitting that the conversion
of Water into air is effected by the intimate union of
what is called the principle of heat with the Water, it
appears sufficiently analogous to other changes, or rather
combinations, of substances. Is not, says Dr. Priestley,
the acid of nitre, and also that of vitriol, a thing as
unlike to air as Water is, their properties being as
remarkably different? And yet it is demonstrable
that the acid of nitre is convertible into the purest
respirable air, and probably by the union of the same
principle of heat. Philos. Trans. vol. 73, p. 414 &c.

Indeed there seems to be Water in all bodies, and
particles of almost all kinds of matter in Water; so that
it is hardly ever sufficiently pure to be considered as an
element. Water, if it could be had alone, and pure,
Boerhaave argnes, would have all the requisites of an
element, and be as simple as fire; but there is no expedient
hitherto discovered for procuring it so pure.
Rain Water, which seems the purest of all those we
know of, is replete with infinite exhalations of all kinds,
which it imbibes from the air: so that if siltered and
distilled a thousand times, there still remain fæces.
Besides this, and the numberless impurities it acquires
after it is raised, by mixing with all sorts of effluvia in
the atmosphere, and by falling upon and running over
the earth, houses, and other places. There is also fire
contained in all Water; as appears from its fluidity,
which is owing to fire alone. Nor can any kinds of
siltering through sand, stone, &c, free it entirely from
salts &c. Nor have all the experiments that have been
invented by the philosophers, ever been able to derive
Water perfectly pure. Hence Boerhaave says, that he
is convinced nobody ever saw a drop of pure Water;
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that the utmost of its purity known, only amounts to
its being free from this or that sort of matter; and that
it can never, for instance, be quite deprived of salt;
since air will always accompany Water, and air always
contains salt.

Water seems to be diffused everywhere, and to be present
in all space wherever there is matter. There are
hardly any bodies in nature but what will yield Water:
it is even asserted that fire itself is not without it. A
single grain of the fiery salt, which in a moment's time
will penetrate through a man's hand, readily imbibes
half its weight of Water, and melts even in the driest
air imaginable. Among innumerable instances, hartshorn,
kept 40 years, and turned as hard and dry as
any metal, so that it will yield sparks of fire when
struck against a flint, yet being put into a glass vessel,
and distilled, will afford 1/8th part of its quantity of
Water. Bones dead and dried 25 years, and thus
become almost as hard as iron, yet by distillation have
yielded half their weight of Water. And the hardest
stones, ground and distilled, always discover a portion
of it. But hitherto no experiment shews, that Water
enters as a principle into the combination of metallic
matters, or even into that of vitrescible stones.

From such considerations, philosophers have been led
to hold the opinion, that all things were made of Water.
Basil Valentine, Paracelsus, Van Helmont, and others
have maintained, that Water is the elemental matter
or stamen of all things, and suffices alone for the production
of all the visible creation. Thus too Newton:
“All birds, beasts, and fishes, insects, trees, and
vegetables, with their several parts, do grow out of
Water, and watery tinctures, and salts; and by putrefaction
they all return again to watery substances.”
And the same doctrine is held, and confirmed by experiments,
by Van Helmont, Boyle, and others.

But Dr. Woodward endeavours to shew that the
whole is a mistake.—Water containing extraneous corpuscles,
some of which, according to him, are the
proper matter of nutrition; the Water being still
found to afford so much the less nourishment, the more
it is purified by distillation. So that Water, as such,
does not seem to be the proper nutriment of vegetables;
but only the vehicle which contains the nutritious
particles, and carries them along with it, through all
the parts of the plant.

Helmont however carries his system still farther, and
imagines that all bodies may be reconverted into Water.
His alkahest, he affirms, adequately resolves plants,
animals, and minerals, into one liquor, or more, according
to their several internal differences of parts;
and the alkahest, being abstracted again from these
liquors, in the same weight, and with the same virtues,
as when it dissolved them, the liquors may, by frequent
cohobations from chalk, or some other proper matter,
be totally deprived of their seminal endowments, and at
last return to their first matter; which is insipid Water.

Spirit of wine, of all other spirits, seems freest from
Water: yet Helmont affirms, it may be so united with
Water, as to become Water itself. He adds, that it
is material Water, only under a sulphureous disguise.
And the same thing he observes of all salts, and of
oils, which may be almost wholly changed into Water.

No standard for the Weight and Purity ofWater.—
Water scarce ever continues two moments exactly
of the same weight; by reason of the air and fire contained
in it. The expansion of Water in boiling shews
what effect the different degrees of fire have on the
gravity of Water. This makes it difficult to fix the
specific gravity of Water, in order to settle its degree
of purity. However, the purest Water we can obtain,
according to the experiments of M. Hawskbee,
is 850 times heavier than air: or according to the experiments
of Mr. Cavendish, the thermometer being
at 50° and the barometer at 29 3/4, about 800 times as
heavy as air: and according to the experiments of Sir
Geo. Shuckburgh, when the barometer is at 29.27 and
the thermometer at 53°, Water is 836 times heavier
than air; whence also may be deduced this general
proportion, which may be accounted a standard, viz,
that, when the barometer is at 30° and the thermometer
at 55°, then Water is 820 times heavier than air; also
that in such a state the cubic foot of Water weighs 1000
ounces avoirdupois, and that of air 1.222, or 1 2/9 nearly,
also that of mercury 13600 ounces; and for other states
of the thermometer and barometer, the allowance is
after this rate, viz, that the column of mercury in the
barometer varies its length by the 10 thousandth part
of itself for a change of each single degree of temperature,
and Water changes by 3/20000 part of its height
or magnitude by each degree of the same. However,
we have not any very exact standard in air; for Water
being so much heavier than air, the more Water there
is contained in the air, the heavier of course must the
air be; as indeed a considerable part of the weight of the
atmosphere seems to arise from the Water that is in it.

Properties and Effects ofWater.—Water is a
very volatile body. It is entirely reduced into vapours
and dissipated, when exposed to the fire and
unconfined.

Water heated in an open vessel, acquires no more
than a certain determinate degree of heat, whatever be
the intensity of the fire to which it is exposed; which
greatest degree of heat is when it boils violently.

It has been found that the degree of heat necessary
to make Water boil, is variable, according to the purity
of the Water and the weight of the atmosphere. The
following table shews the degree of heat at which Water
boils, at various heights of the barometer, being a medium
between those resulting from the experiments of
Sir Geo. Shuckburgh and M. De Luc:

Height of the

Heat of Boiling

Barometer.

Water.

Inches.

°

26

205

26 1/2

206

27

206.9

27 1/2

207.7

28

208.5

28 1/2

209.4

29

210.3

29 1/2

211.2

30

212.0

30 1/2

212.8

31

213.6

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Water is found the most penetrative of all bodies,
after fire, and the most difficult to confine; passing
through leather, bladders, &c, which will confine air;
making its way gradually through woods; and is only
retainable in glass and metals; nay it was found by
experiment at Florence, that when shut up in a spherical
vessel of gold, which was pressed with a great force,
it made its way through the pores even of the gold
itself.

Water, by this penetrative quality alone, may be inferred
to enter the composition of all bodies, both vegetable,
animal, fossil, and even mineral; with this particular
circumstance, that it is easily, and with a gentle
heat, separable again from bodies it had united with.

And yet the same Water, as little cohesive as it is,
and as easily separated from most bodies, will cohere
firmly with some others, and bind them together in
the most solid masses; as in the tempering of earth, or
ashes, clay, or powdered bones, &c, with Water, and
then dried and burnt, when the masses become hard
as stones, though without the Water they would be
mere dust or powder. Indeed it appears wonderful
that Water, which is otherwise an almost universal
dissolvent, should nevertheless be a great coagulator.

Some have imagined that Water is incompressible,
and therefore nonelastic; founding their opinion on
the celebrated Florentine experiment above mentioned,
with the globe of gold; when the Water being, as
they say, incapable of condensation, rather than yield,
transuded through the pores of the metal, so that the
ball was found wet all over the outside; till at length
making a clest in the gold, it spun out with great vehemence.
But the truth of the conclusions drawn from
this Florentine experiment has been very justly questioned;
Mr. Canton having proved by accurate experiments,
that Water is actually compressed even by
the weight of the atmosphere. See Compression.

Besides, the diminution of size which Water suffers
when it passes to a less degree of heat, sufficiently
shews that the particles of this fluid are, like those of
all other known substances, capable of approaching
nearer together.

DitchWater, is often used as an object for the
microscope, and seldom fails to afford a great variety
of animalcules; often appearing of a greenish, reddish,
or yellowish colour, from the great multitudes of them.
And to the same cause is to be ascribed the green skim
on the surface of such Water. Dunghill Water is also
full of an immense crowd of animalcules.

FreshWater, is said of that which is insipid, or
without salt, and inodorous; being the natural and
pure state of the element.

HardWater, or CrudeWater, is that in which
soap does not dissolve completely or uniformly, but is
curdled. The dissolving power of hard Water is less
than that of soft; and hence its unfitness for washing,
bleaching, dyeing, boiling kitchen vegetables, &c.

The hardness of Water may arise either from salts,
or from gas. That which arises from salts, may be
discovered and remedied by adding some drops of a
solution of fixed alkali; but the latter by boiling, or
exposure to the open air.

Spring Waters are often hard; but river Water soft.
Hard Waters are remarkably indisposed to corrupt;
they even preserve putrescible substances for a considerable
length of time: hence they seem to be best fitted
for keeping at sea, especially as they are so easily softened
by a little alkaline salt.

PutridWater, is that which has acquired an offensive
smell and taste by the putrescence of animal or
vegetable substances contained in it. This kind of
Water is in the highest degree pernicious to the human
frame, and capable of bringing on mortal diseases even
by its smell. Quicklime put into water is useful to
preserve it longer sweet; or even exposure to the air
in broad shallow vessels. And putrid Water may be
in a great measure sweetened, by passing a current of
fresh air through it, from bottom to top.

RainWater may be considered as the purest distilled
Water, but impregnated during its passage through
the air with a considerable quantity of phlogistic and
putrescent matter; whence it is superior to any other
in fertilizing the earth. Hence also it is inferior for
domestic purposes to spring or river Water, even if it
could be readily procured: but such as is gotten from
spouts placed below the roofs of houses, the common
way of procuring it in this country, is evidently very
impure, and becomes putrid in a short time.

River or RunningWater, is next in purity to snow
or distilled water; and for domestic purposes superior
to both, in having less putrescent matter, and more
fixed air. That however is much the purest that runs
over a clean rocky or stony bottom.

River Waters generally putrefy sooner than those of
springs. During the putrefaction, they throw off a
part of their heterogeneous matter, and at length become
sweet again, and purer than at first; after which
they commonly preserve a long time: this is remarkably
the case with the Thames Water, taken up about London;
which is commonly used by seamen, in their
voyages.

SaltWater, such as has much salt in it, so as to
be sensible to the taste.

SeaWater, or Water of the sea, is an assemblage
of bodies, in which Water can scarce be said to have
the principal part: it is an universal colluvies of all
the bodies in nature, sustained and kept swimming in
Water as a vehicle: being a solution of common salt,
sal catharticus amarus, a selenitic substance, and a compound
of muriatic acid with magnesia, mixed together
in various proportions. It may be freshened by simple
distillation without any addition, and thus it has sometimes
been useful in long voyages at sea. Sea Water
by itself has a purgative quality, owing to the salts it
contains; and has been greatly recommended in scrophulous
disorders.

Sea Water is about 3 parts in 100 heavier than common
Water; and its temperature at great depths is
from 34 to 40 degrees; but near the surface it follows
more nearly the temperature of the air.

SnowWater, is the purest of all the common
Waters, when the snow has been collected pure. Kept
in a warm place, in clean glass vessels, not closely
stopped, but covered from dust, &c, snow water becomes
in time putrid; though in well-stopped bottles
it remains unaltered for several years. But distilled
Water suffers no alteration in either circumstance.

SpringWater is commonly impregnated with a
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small portion of imperfect neutral salt, extracted from
the different strata through which it percolates. Some
contain a vast quantity of stony matter, which they
deposit as they run along, and thus form masses of
stone; sometimes incrustating various animal and vegetable
matters, which they are therefore said to petrify.
Spring-Water is much used for domestic purposes, and
on account of its coolness is an agreeable drink; but
on account of its being usually somewhat hard, is inferior
to that which has run for a considerable way in a
channel.

Spring-water arises from the rain, and from the
mists and moisture in the atmosphere. These falling
upon hills and other parts of the earth, soak into the
ground, and pass along till they find a vent out again, in
the form of a spring.

Water-Bellows, in Mechanics, are bellows, for
blowing air into furnaces, that are worked by the force
of water.

Water-Clock. See Clepsydra.

Water-Engine, an engine for extinguishing fires;
or any engine to raise water; or any engine moved by
the force of Water. See Engine, and Steam-Engine.

Water-Gage, an instrument for measuring the
depth or quantity of any water. See Gage.

Water-Level, is the true level which the surface of
still Water takes, and is the truest of any.

Water-Logged, in Sea-Language, denotes the state
of a ship when, by receiving a great quantity of Water
into her hold, by leaking, &c, she has become heavy
and inactive upon the sea, so as to yield without resistance
to the effort of every wave rushing over her
deck.

Water-Machine. See Machine.

Water-Measure. Salt, sea-coal, &c, while on
board vessels in the pool, or river, are measured with
the corn-bushel heaped up; or else 5 striked pecks are
allowed to the bushel. This is called Water-measure;
and it exceeds Winchester-measure by about 3 gallons in
the bushel.

Water-Microscope. See Microscope.

Water-Mill. See Mill.

Motion ofWater, in Hydraulics. The theory of
the motion of running Water is one of the principal
objects of hydraulics, and to which many eminent mathematicians
have paid their attention. But it were to
be wished that their theories were more consistent with
each other, and with experience. The inquisitive reader
may consult Newton's Principia, lib. 2, pr. 36, with
the comment. Dan. Bernoulli's Hydrodynamica. J.
Bernoulli, Hydraulica, Oper. tom. 4, pa. 389. Dr.
Jurin, in the Philos. Trans. num. 452, or Abridg.
vol. 8, pa. 282. Gravesande, Physic. Elem. Mathem.
lib. 3, par. 2. Maclaurin's Flux. art. 537. Poleni de
Castellis, Ximenes, D'Alembert, Bossu, Buat, and
many others.

But notwithstanding the labours of all these eminent
authors, this intricate subject still remains in a great
measure obscure and uncertain. Even the simple case of
the motion of running water, when it issues from a
hole in the bottom of a vessel, has never yet been determined,
so as to give universal satisfaction to the learned.
On this head, it is now pretty generally allowed,
that the velocity of the issuing stream, is equal to that
which a heavy body acquires by falling through the
height of the fluid above the hole, as may be demonstrated
by theory: but in practice, the quantity of the
effluent Water is much less than what is given by this
theory; owing to the obstruction to the motion in the
hole, partly from the sides of it, and partly from the
different directions of the parts of the Water in entering
it, which thence obstruct each other's motion. And
this obstruction, and the diminution in the quantity of
Water run out, is still the more in proportion as the
hole is the smaller; in such sort, that when the hole is
very small, the quantity is diminished in the ratio of √2
to 1 very nearly, which is the ratio of the greatest diminution;
and for larger holes, the diminution is always
less and less. This fact is ascertained, or admitted
by Newton, and all the other philosophers abovementioned,
with some small variations.

That the velocity of the Water in the hole, or at
least some part of it, as that for example in the middle
of the stream, is equal to that abovementioned, is even
evinced by experiment, by directing the stream either
sideways, or upwards: for in the former case, it is
found to range upon an horizontal plane, a distance
that just answers to that velocity, by the nature of projectiles;
and in the latter case, the jet rises nearly to
the height of the Water in the vessel; which it could
not do, if its velocity were not equal to that acquired
by the free descent of a body through that height.
Hence it is evident then, that the particles of the Water,
which are in the hole at the same moment of time,
do not all burst out with the same velocity; and, in fact,
the velocity is found to decrease all the way from the
middle of the hole, where it is greatest, towards the
side or edge, where it is the least.

At a small distance from the hole, the diameter of the
vein of Water is much less than that of the hole. Thus,
if the diameter of the hole be 1, the diameter of the
vein of Water just without it, will be 21/25, or 0.84, according
to Newton's measure, who first observed this
phenomenon; and according to Poleni's measure 0.78
nearly.

By the experiments of Buat (Principes d'Hydraulique),
the quantity by theory is to that by experiment,
for a small hole made in the thin side of a reservoir, as
8 to 5. When a short pipe is added to the hole outwards,
of the length of two or three times its diameter,
that ratio is as 16 to 13. And when
the short pipe is all within side the
vessel, as in the margin, the same
ratio becomes that of 3 to 2. Poleni
also found that the quantity of Water
flowing through a pipe or tube, was
much greater than that through a
hole of the same diameter in the thin
side or bottom of the vessel, the
height of the head of Water above
each being the same. See also many other curious circumstances
in Buat's Principes above mentioned.

Some authors give this rule for finding the height
due to the velocity in a flat orifice, or a medium among
all the parts of it, such that this medium velocity being
drawn into the area of the hole, shall give the quantity
per second that runs through: viz, let A denote the
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area of the surface of the Water in the vessel, a the
area of the orifice by which the Water issues, and H
the height of the Water above the orifice; then,
as 2A - a : A :: H : b, the height due to the medium
velocity, or the height from which a body must freely
descend, by the force of gravity, to acquire that mean
velocity.

Authors are not yet agreed as to the force with which
a vein of Water, spouting from a round hole in the side
of a vessel, presses upon a plane directly opposed to the
motion of the vein. Most authors agree, that the
pressure of this vein, flowing uniformly, ought to be
equal to the weight of a cylinder of Water, whose base
is equal to the hole through which the Water flows, and
its height equal to the height of the Water in the vessel
above the hole. The experiments made by Mariotte,
and others, seem to countenance this opinion. But
Dan. Bernoulli rejects it, and estimates this pressure by
the weight of a column of the fluid, whose diameter is
equal to the contracted vein (according to Newton's
observation abovementioned), and the height of which
is equal to double the altitude due to the real velocity of
the spouting Water; and this pressure is also equal to
the force of repulsion, arising from the reaction of the
spouting Water upon the vessel. The ingenious author
remarks that he speaks only of single veins of Water,
the whole of which are received by the planes upon
which they press; for as to the pressures exerted by
fluids surrounding the bodies they press upon, as the
wind, or a river, the case is different, though confounded
with the former by writers on this subject. Hydrodynamica,
pa. 289.

Another rule however had been adopted by the Academicians
of Paris, who made a number of experiments
to confirm or establish it. Hist. Acad. Paris,
ann. 1679, sect. 3, cap. 5.

D. Bernoulli, on the other hand, thinks his own
theory sufficiently established by the experiments he relates;
for the particulars of which see the Acta Petropolitana,
vol. 8, pa. 122.

This ingenious author is of opinion that his theory of
the quantity of the force of repulsion, exerted by a vein
of spouting Water, might be usefully applied to move
ships by pumping; and he thinks the motion produced
by this repulsive force would fall little, if at all, short
of that produced by rowing. He has given his reasons
and computations at length in his Hydrodynamica,
pa. 293 &c.

This science of the pressures exerted by Water or
other fluids in motion, is what Bernoulli calls Hydraulico-statica.
This science differs from hydrostatics,
which considers only the pressure of Water and other
fluids at rest; whereas hydraulico-statics considers the
pressure of Water in motion. Thus the pressure exerted
by Water moving through pipes, upon the sides of
those pipes, is an hydraulico-statical consideration, and
has been erroneously determined by many, who have
given no other rules in these cases, but such as are applicable
only to the pressure of fluids at rest. See
Hydrodynam. pa. 256 &c.

Water-Poise. See Hydrometer, and AREOMETER.

Dr. Hook contrived a Water-poise, which may be of
good service in examining the purity &c of Water. It
consists of a round glass ball, like a bolt head, about
3 inches diameter, with a narrow stem or neck, the
24th of an inch in diameter; which being poised with
red lead, so as to make it but little heavier than pure
sweet Water, and thus fitted to one end of a fine balance,
with a counterpoise at the other end; upon the
least addition of even the 2000th part of salt to a quantity
of Water, half an inch of the neck will emerge
above the water. Philos. Trans. num. 197.

Raising ofWater, in Hydraulics. The great use
of raising Water by engines for the various purposes of
life, is well known. Machines have in all ages been
contrived with this view; a detail of the best of which,
with the theory of their construction, would be very
curious and instructive. M. Belidor has executed this
in part in his Architecture Hydraulique. Dr. Desaguliers
has also given a description of several engines to
raise Water, in his Course of Experimental Philosophy,
vol. 2, and there are several other fmaller works of the
same kind.

Engines for raising Water are either such as throw
it up with a great velocity, as in jets; or such as raise it
from one place to another by a gentle motion. For
the general theory of these engines, see Bernoulli's
Hydrodynamica.

Desaguliers has settled the maximum of engines for
raising water, thus: a man with the best Water engine
cannot raise above one hogshead of Water in a minute,
10 feet high, to hold it all day; but he can do almost
twice as much for a minute or two.

Water-Spout. See Spout.

Water-Wheel, an engine for raising Water in
great quantity out of a deep well, &c. See Persian-
Wheel.

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